Return-path: Received: from mail.tpi.com ([70.99.223.143]:1673 "EHLO mail.tpi.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752170Ab1AROtj (ORCPT ); Tue, 18 Jan 2011 09:49:39 -0500 Message-ID: <4D35A87D.3020600@canonical.com> Date: Tue, 18 Jan 2011 07:49:33 -0700 From: Tim Gardner Reply-To: tim.gardner@canonical.com MIME-Version: 1.0 To: Stanislaw Gruszka CC: stable@kernel.org, Dominik Brodowski , linux-wireless@vger.kernel.org Subject: Re: [PATCH 2.6.32.y] hostap_cs: fix sleeping function called from invalid context References: <1295269524-4937-1-git-send-email-sgruszka@redhat.com> In-Reply-To: <1295269524-4937-1-git-send-email-sgruszka@redhat.com> Content-Type: multipart/mixed; boundary="------------010209070803070307000301" Sender: linux-wireless-owner@vger.kernel.org List-ID: This is a multi-part message in MIME format. --------------010209070803070307000301 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit On 01/17/2011 06:05 AM, Stanislaw Gruszka wrote: > commit 4e5518ca53be29c1ec3c00089c97bef36bfed515 upstream. > > pcmcia_request_irq() and pcmcia_enable_device() are intended > to be called from process context (first function allocate memory > with GFP_KERNEL, second take a mutex). We can not take spin lock > and call them. > > It's safe to move spin lock after pcmcia_enable_device() as we > still hold off IRQ until dev->base_addr is 0 and driver will > not proceed with interrupts when is not ready. > > Patch resolves: > https://bugzilla.redhat.com/show_bug.cgi?id=643758 > > Reported-and-tested-by: rbugz@biobind.com > Signed-off-by: Stanislaw Gruszka > --- > drivers/net/wireless/hostap/hostap_cs.c | 10 ++-------- > 1 files changed, 2 insertions(+), 8 deletions(-) > > diff --git a/drivers/net/wireless/hostap/hostap_cs.c b/drivers/net/wireless/hostap/hostap_cs.c > index b4ff1dc..6992f8f 100644 > --- a/drivers/net/wireless/hostap/hostap_cs.c > +++ b/drivers/net/wireless/hostap/hostap_cs.c > @@ -662,12 +662,6 @@ static int prism2_config(struct pcmcia_device *link) > link->dev_node =&hw_priv->node; > > /* > - * Make sure the IRQ handler cannot proceed until at least > - * dev->base_addr is initialized. > - */ > - spin_lock_irqsave(&local->irq_init_lock, flags); > - > - /* > * Allocate an interrupt line. Note that this does not assign a > * handler to the interrupt, unless the 'Handler' member of the > * irq structure is initialized. > @@ -690,9 +684,10 @@ static int prism2_config(struct pcmcia_device *link) > CS_CHECK(RequestConfiguration, > pcmcia_request_configuration(link,&link->conf)); > > + /* IRQ handler cannot proceed until at dev->base_addr is initialized */ > + spin_lock_irqsave(&local->irq_init_lock, flags); > dev->irq = link->irq.AssignedIRQ; > dev->base_addr = link->io.BasePort1; > - > spin_unlock_irqrestore(&local->irq_init_lock, flags); > > /* Finally, report what we've done */ > @@ -724,7 +719,6 @@ static int prism2_config(struct pcmcia_device *link) > return ret; > > cs_failed: > - spin_unlock_irqrestore(&local->irq_init_lock, flags); > cs_error(link, last_fn, last_ret); > > failed: Yes - I think this patch is correct. I didn't drill deep enough to notice the GFP_KERNEL memory allocation. However, I think there is still a problem with the interrupt handler which will only be noticed if there is another active device on the same shared interrupt. Shouldn't it return IRQ_NONE? See attached. rtg -- Tim Gardner tim.gardner@canonical.com --------------010209070803070307000301 Content-Type: text/x-patch; name="0001-hostap-Return-IRQ_NONE-if-the-device-has-not-been-co.patch" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename*0="0001-hostap-Return-IRQ_NONE-if-the-device-has-not-been-co.pa"; filename*1="tch" >From 638d3ea93e2a9cccb860d9e31c84e5d3a3eb38bd Mon Sep 17 00:00:00 2001 From: Tim Gardner Date: Tue, 18 Jan 2011 07:47:45 -0700 Subject: [PATCH] 2.6.32.y, hostap: Return IRQ_NONE if the device has not been configured Signed-off-by: Tim Gardner --- drivers/net/wireless/hostap/hostap_hw.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/drivers/net/wireless/hostap/hostap_hw.c b/drivers/net/wireless/hostap/hostap_hw.c index 8721850..789a503 100644 --- a/drivers/net/wireless/hostap/hostap_hw.c +++ b/drivers/net/wireless/hostap/hostap_hw.c @@ -2624,7 +2624,7 @@ static irqreturn_t prism2_interrupt(int irq, void *dev_id) printk(KERN_DEBUG "%s: Interrupt, but dev not configured\n", dev->name); } - return IRQ_HANDLED; + return IRQ_NONE; } iface = netdev_priv(dev); -- 1.7.0.4 --------------010209070803070307000301--